In the production of stamped or pressed metal parts, stamping press lines may be supplied with metal blanks that have previously been cut from a metal coil in a separate blanking line. The blanks may be shear-cut metal blanks of a predetermined length or they may be contoured blanks cut with a blanking die.
The use of industrial robots for picking blanks from a stack at a pick-up position and loading them in a stamping press line, such as those for manufacturing vehicle body parts is known.
In known systems, a first industrial loading robot collects the blanks from a stack of blanks. The blanks at the top of the stack e.g. blanks made of magnetic material may be maintained slightly separated from each other at least at the edges, for example by magnets, to prevent them from adhering to each other and thus preventing the first loading robot from picking more than one blank, which would cause serious problems.
The first industrial robot situates the blank located at the top of the stack in a centering station e.g. a gravity table to get the blank centered. Alternatively, the blank may be located using e.g. a vision system. A second industrial loading robot collects the centered or located blank and feeds the blank to the head press of the stamping press line. Centering or locating of the blanks is generally required because the stacks of blanks may be inaccurately placed in the pick-up position by a forklift truck, and also because of the inaccurate position of the stack on the supporting element e.g. pallet which doesn't allow for the accuracy needed to load the blank into a press.
With this arrangement, at least two industrial robots and a centering device are required for the de-stacking and loading operation.
In low cost and/or low output rate requirement cases, it might be desirable to provide a simpler solution that allows working with a single loading robot, and at the same time removing the need for a costly centering or locating system.